In bag-shaped (flexible pouch) beverage containers having a membrane seal which is to be pierced by a pointed straw, such as CAPRI SUb.RTM. or like containers which are shown in U.S. Pat. No. 3,380,646 (Doyen et al.), there is a problem of providing a sufficiently strong membrane seal to withstand the rigors of shipping while still making the membrane seal sufficiently easy for the consumer to pierce with a straw. The piercing of the membrane seal may be a particular problem for small children who frequently utilize such containers and who lack the dexterity of adults.
Typical of opening systems in the prior art are those where a small hole is provided in a barrier wall of the container, with the hole then being covered with a pierceable membrane seal. While such a membrane seal is mostly satisfactory, it is often difficult for young children (ages 4-9) to use since the membrane must be struck with the straw only in the hole in the barrier wall and at the same time with somewhat of a downward angle so that the straw does not pierce as well the back barrier wall of the container. In addition, as the membrane seal is pierced, squeezing of the bag-shaped container to hold the container steady during piercing may result in the beverage being pushed up around the outside of the straw and out of the straw hole causing undesired spillage.